Braking and Propulsion Phase Characteristics of Traditional and Accentuated Eccentric Loaded Back Squats

Authors

Timothy J. Suchomel, Carroll University
Conor J. Cantwell, Carroll University
Brookelyn A. Campbell
Zach S. Schroeder, Carroll University
Lauren K. Marshall, Carroll University
Christopher Taber, Sacred Heart UniversityFollow

Document Type

Peer-Reviewed Article

Publication Date

2024

Abstract

The purpose of this study was to examine the differences in braking and propulsion force-time characteristics and barbell velocity between traditional (TRAD) and accentuated eccentric loaded (AEL) back squats using various load combinations. Sixteen resistance-trained men participated in four separate testing sessions which included a one repetition maximum (1RM) back squat during the first session and three squat testing sessions. During the squat testing sessions, participants either performed sets of three repetitions of TRAD back squats each with 50, 60, 70, and 80% 1RM or performed the same loads with the addition of weight releasers that increased the total eccentric weight of the first repetition of each set to either 100 (AEL-MAX) or 110% 1RM (AEL-SUPRA). Braking and propulsion mean force, duration, and impulse as well as mean and peak barbell velocity were compared between each condition and load. Significantly greater braking impulses were produced during the AEL-MAX and AEL-SUPRA conditions compared to TRAD (p < 0.03) with small-moderate effect sizes favoring AEL-SUPRA. No other significant differences existed among conditions for other braking, propulsion, or barbell velocity variables. AEL-MAX and AEL-SUPRA back squats may provide a greater braking stimulus compared to TRAD squats; however, the propulsion phase of the movement does not appear to be impacted. From a loading standpoint, larger and smaller load spreads may favor rapid and maximal force production characteristics, respectively. Further research on this topic is needed as a large portion of the braking stimulus experienced during AEL back squats may be influenced by relative strength.

Comments

Open access Creative Commons CC BY 4.0 license

DOI

10.5114/jhk/185726

Recommended Citation

Suchomel, T. J., Cantwell, C. J., Campbell, B. A., Schroeder, Z. S., Marshall, L. K., Taber, C. B. (2024). Braking and propulsion phase characteristics of traditional and accentuated eccentric loaded back squats. Journal of Human Kinetics, 91, 121-133. Doi:10.5114/jhk/185726

Creative Commons License

This work is licensed under a Creative Commons Attribution 4.0 International License.